Pump anchors



Dec. 31, 1968 D. T. HARBISON ETAL PUMP ANCHORS Sheet of 5 Filed Nov. 29, 1965 Dixon T Hcrbison James A Burns ATTORNEYS I 1968 D. T. HARBISON ETAL 3,

PUMP ANCHORS z of 5 Sheet Filed Nov. 29, 1965 lNVEN TORS Dlxon I1 Horbnson, James A. Burns 5 FIG. 6-A

FIG. 5

ATTORNEYS Dec. 31, 1968 D. 'r. HARBISON ETAL 3,419,073

PUMP ANCHORS Filed Nov. 29, 1965 Sheet 3 of 5 INVENTORS DixonT Horbison' James A. Burns Dec. 31, 1968 Filed Nov. 29, 1965 D. T. HARBISON ETAL PUMP AN'CHORS Sheet i of 5 F I G. l9

Dixon T Ha r i g James A.Burns ATTORNEYS United States Patent 3,419,078 PUMP ANCHORS Dixon T. Harbison and James A. Burns, Fort Worth, Tex., assignors to Harbison-Fischer Manufacturing (10., Fort Worth, Tex., a corporation of Texas Filed Nov. 29, 1965, Ser. No. 510,330 3 Claims. (Cl. 166-138) ABSTRACT OF THE DISCLOSURE A well pump anchor having a packing means and having means for preventing overly secure setting of the anchor in the wellbore which would make its removal difiicult or maybe impossible and also having means for preventing jamming of the anchor in the wellbore as it is being removed by reason of the upper end of the resilient packing sleeve encountering paraflin or some other obstruction in the wellbore and being unintentionally expanded and stuck in the wellbore by being forced downwardly.

This invention is an improvement on that disclosed in our US. Letters Patent No. 3,195,643, issued July 20, 1965, and reference is made thereto.

The invention relates to new and useful improvements in pump anchors.

Under some conditions the pump anchors of the above patent can malfunction, and the present invention is directed toward eliminating such possibilities.

In the first instance, when the pump and the pump anchor are being withdrawn from the wellbore, especially at relatively rapid rate, an area of accumulated parafiin in the tubing may be encountered, and as the pump anchor moves upwardly, the upper end of the distortable packing member may engage such paraffin, causing the packing member to distort longitudinally and wedge in the tubing, preventing continued withdrawal of the pump anchor. It is, therefore, one object of this invention to provide an improved pump anchor in which the packing member has its upper end secured to the mandrel of the pump anchor and thus held against downward distortion under such circumstances and thereby precluding the possibility that the packing member will be inadvertently wedged in the tubing.

In the second instance, the sucker or pump rods operating the pump in conjunction with which the pump anchor is used, may break due to wear, fatigue, or other conditions, and if this occurs, the entire weight of the pump and of the sucker rods below the point of fracture will fall upon the pump anchor, thereby causing the tapered wedge member to telescope excessively far into the tubing gripping members and so firmly lock the pump anchor in position as to preclure its subsequent removal. If this occurs, it becomes necessary to mechanically ream or broach the tubing and the pump anchor from the well bore.

It is, therefore, a further object of the invention to provide an improved pump anchor having positive means for preventing excessive penetration of the wedge member into the tubing gripping means.

Other and more particular objects of the invention will be apparent from a reading of the following description.

A construction designed to carry out the invention will be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by referencee to the accompanying drawings, wherein an example of the invention is shown, and wherein:

FIG. 1 is a side elevational view of a pump anchor constructed in accordance with the aforesaid patent and showing the anchor in an unset position,

FIG. 2 is an enlarged, vertical, sectional view of the pump anchor in an unset position,

FIG. 2-A is a continuation of FIG. 2,

FIG. 3 is an enlarged cross-sectional view taken upon the line 3-3 of FIG. 1,

FIG. 4 is an enlarged cross-sectional view taken upon the line 44 of FIG. 1,

FIG. 5 is a side elevational view of the pump anchor showing it in its set position,

FIG. 6 is an enlarged, vertical, sectional view of the pump anchor in its set condition,

FIG. 6A is a continuation of FIG. 6,

FIG. 7 is an enlarged, cross-sectional view taken on the line 77 of FIG. 2A,

FIG. 8 is an enlarged, cross-sectional view taken on the line 8-8 of FIG. 6A,

FIG. 9 is an enlarged, cross-sectional View taken on the line 99 of FIG. 6,

FIG. 10 is an enlarged, cross-sectional view taken on the line 1010 of FIG. 2,

FIG. 11 is an enlarged, cross-sectional view taken on the line 11-11 of FIG. 1,

FIG. 12 is a vertical, sectional view showing the improved pump anchor constructed in accordance with this invention in an unset position,

FIG. 13 is a vertical view, partly in elevation and partly in section, showing the improved pump anchor in a set position,

FIGS. 14 and 15 are enlarged, cross-sectional views taken upon the respective lines of FIG. 13,

FIG. 16 is a view in perspective of the annular cuplike member which limits telescoping of the wedge element into the tubing gripping elements,

FIG. 17 is an enlarged, fragmentary, vertical, sectional view showing the position of the wedge element and the tubing gripping elements with the pump anchor in an unset position,

FIG. 18 is a view similar to FIG. 17, showing the anchor in a set position, and

FIG. 19 is an enlarged, vertical, sectional view showing the upper end of the packing member and the manner in which it is secured to the mandrel.

FIGS. 1 through 11 disclose the pump anchor of our US. Patent No. 3,195,643.

In the drawings, the numeral 10 designates a conventional well tubing positioned within a well bore and within which the pump anchor of this invention is adapted to be utilized. The pump anchor may be lowered into the well tubing in any desired or suitable fashion, the embodiment illustrated including a suitable well pipe 11 having a screwthreaded box 12 at its lower end for receiving the upstanding screwthreaded pin 13 provided upon the upper end of a packing member thimble 14 having at its lower end a beveled seat 15 surrounding a screwthreaded box 16. A lock nut 17 on the neck 13 secures the joint between said neck and the box 12.

An elongate tubular mandrel 18 has its screwthreaded upper end 19 received in the box 16 and projects downwardly throughout the length of the anchor into a screwthreaded coupling or collar 20 at its lower end from which the usual tail pipe 21 extends downwardly in the well tubing.

A packing member is disposed on the mandrel beneath the thimble 14 and includes an elongate, annular body 22 formed of rubber or a rubber-like or other distortable material and having an axial bore 23. The end faces 24 of the body 22 are convergent, the upper face being upwardly convergent toward the axial bore 23 and the lower face being downwardly convergent toward the bore. End caps are provided for the packer body 22 and include tubular sleeves 25 having an internal bore 26 approximately equal in diameter to the axial bore 23 and being recessed and bonded in the end portions of the body 22. The sleeves 25 carry annular outwardly extending flanges 27 at their exposed ends, the flanges having inner faces 28 angularly disposed to conform to the end faces 24 of the body 22 and approximately parallel outer faces 29 complementary to the beveled lower end of the thimble 14. The end caps are identical so that the packing member is reversible upon the mandrel 18. The inner or inside faces 28 of the flanges 27 are also bonded to the end faces of the packer body 22, and for additional safeguarding against leakage or seepage into the interior of the packing member, the sleeves carry internal O-ring grooves 30 facing inwardly toward the mandrel 18, and each of the O-ring grooves 30 receives a sealing O-ring 31 which engages the outer surface of the mandrel and seals thereagainst. Thus, liquid cannot seep or leak between the packer body 22 and the sleeves 25 due to the bonding of the sleeves to the packer body, nor can liquid seep between the sleeves and the mandrel due to the presence of the sealing O-rings 31.

A setting assembly surrounds the mandrel 18 below the packing member and includes friction shoe means 32 having an elongate tubular body member 33 with an axial bore 34 within which the mandrel 18 is longitudinally movable. Intermediate the ends of the bore 34, the body member carries an integral internal shoulder 35 having cut therein diametrically opposed, longitudinal grooves or notches 36. An inverted J-slot 37 is cut through the wall of the body member 33, and a pin 38 projecting radially outwardly from the mandrel 18 engages in the J-slot 37 in order that longitudinal movement of the setting assembly 32 upon the mandrel 18 may be controlled as desired.

The body member 33 has formed therein a plurality of longitudinal external grooves 39 extending from a point closely adjacent its lower end to a point closely adjacent its upper end, and within each of the grooves 39 is mounted a pair of longitudinally alined spring shoes 40 having outwardly bowed center sections 41 and short rectilinear end portions 42. The lower end of the body 33 is reduced in diameter to form an annular, external, downwardly facing shoulder 43 and has its lower extremity further reduced to form a depending screwthreaded pin 44 and an annular, external, downwardly facing shoulder 45. A screwthreaded cap 46 is engaged upon the pin 44 with its upper end abutting the shoulder 45, and carries a marginal, upwardly extending flange 47 on its upper end which engages the shoulder 43 and loosely confines the lower rectilinear ends 42 of the spring shoes 40 within the lower portions of the grooves 39.

Intermediate its ends, the friction shoe body 33 is provided with a wide and shallow circumferential groove 48 overlying the medial portions of the grooves 39 and receiving a retaining band 49 which overlies in the grooves the upper rectilinear ends 42 of the lower friction shoes 40 as well as the lower rectilinear ends of the upper set of friction shoes. It is noted that each of the grooves 39 is greater in depth than the thickness of the ends of the friction shoes 40 and that the grooves are greater in overall length than the sum of the lengths of the two friction shoes disposed therein, so that the latter are free to undergo limited longitudinal movement within the grooves as they are flexed by the inner wall of the tubing 10 as well as some lateral movement. Such relative looseness of mounting protects the spring shoes 40 against breakage, permits their quick and ready replacement, and allows their desirable freedom of movement under flexing conditions.

At its upper end, the friction shoe body 33 is also reduced in diameter to provide an external upwardly facing shoulder 50, and still further reduced at its upper extremity to form an upstanding screwthreaded pin 51 and an upwardly facing external shoulder 52. A tubular first setting member 53 has a screwthreaded box 54 in its lower end which receives the pin 51, and also carries a marginal depending flange 55 which seats upon the shoulder and confines in the upper ends of the grooves 39- the upper rectilinear ends of the upper set of friction shoes 40. Again, the friction shoes do not extend entirely to the ends of the grooves 39 and are loosely confined by the skirt for freedom of movement and flexing while being securely retained as a part of the friction shoe member.

Above the box 54, the first setting member 53 is reduced in external diameter and longitudinally slotted to its upper end to form a plurality of upwardly projecting arms 56 which are flexible in nature and capable of being forced outwardly toward the inside wall of the tubing 10. Gripping elements 57 in the form of outwardly facing, transversely grooved or serrated slip faces are formed on the upper ends of the arms 56 and are adapted to be forced outwardly into gripping engagement with the inner wall of the tubing 10. For forcing the gripping elements outwardly as well as gripping the mandrel 18, a second setting member 58 having an axial bore 59 for receiving the mandrel 18, is formed with a frusto-conical lower portion 60 having a relatively small degree of taper and extending downwardly around the mandrel 18 into telescoping engagement within the arms 56 and especially the portions thereof carrying the gripping elements 57. The upper end of the second setting member 58 is enlarged and carries a beveled seat 61 engaging the lower end cap member 25 of the packing member. The second setting member is also slotted longitudinally from a point immediately below its enlarged upper end to a point spaced above its lower end, as indicated at 62, such slotting causing the medial portion of the member 58 to have a degree of flexibility and allowing this portion to be forced inwardly toward the mandrel 18. A plurality of transverse slip teeth or gripping edges 63 are formed on the wall of the axial bore 59 intermediate the upper and lower ends of the slots 62 and are adapted to engage the mandrel 18 in gripping relationship.

The mandrel 18 carries a pair of integral, diametrical- 1y opposed, rectilinear lugs 64 adapted to engage the shoulder 35 when the pin 38 is in the shorter leg of the J-slot 37 and the anchor is in latched condition as shown in FIGS. 1, 2 and 2-A. Thus, the mandrel is held against downward movement in the body member 33, and the pin 38 is protected against being sheared off against the lower end of the shorter leg of the ]-slot 37. When, however, the mandrel is revolved in the body member 33 to shift the pin 38 into the longer leg of the J-slot 37 for unlatching the anchor, the lugs 64 will be moved into alinement with the grooves or notches 36 so that the mandrel is free to move downwardly in the body member 33. Thus, the notched shoulder member and the lugs form a pair of interrupted shoulder means. As the mandrel is moved upwardly during the unlatching operation, the spacing between the bottom cap 46 and the coupling 20 is such that the pin 38 cannot engage the upper end of the shorter leg of the I-slot 37 and be damaged thereby. Of course, the pin 38 can never reach the bottom of the longer leg of the J-slot.

The mandrel 18 has a slightly enlarged portion 65 on its outer surface within the first setting member 53 reduced at its upper end to form a radially outwardly facing step 66 over which the lower frusto-conical end 60 of the second setting member 58 telescopes so as to prevent engagement of the slip teeth 63 with the mandrel until the packing member 22 is fully set and the mandrel has moved further downwardly to withdraw the step 66 from beneath the lower end of the second setting member. It will be noted that in the unset position of the pump anchor in which it is lowered into the well bore, the lower end of the second gripping or setting member 58 abuts the enlarged portion 65 on the madrel 18, as shown in FIG. 2, thus preventing the second setting member 58 from being accidentally forced downardly between the arms 56 and causing premature engagement of the gripping elements 57 with the wall of the tubing 10. As is customary, the upper portions of the arms 56 have an internal bowl-like configuration for receiving the lower end of the second setting member 58.

In use, the anchor assembly, depending from a well pump by means of the pipe or connector 11, is lowered into the tubing with the pin 38 disposed in the bottom portion of the short arm of the J-slot 37. As the anchor moves downwardly through the tubing, the friction shoes 40 in engaging the inside wall of the tubing 10 will tend to cause the friction shoe member 32 and the first setting member 53 to move upwardly over the mandrel, but the engagement of the shoulder 35 with the lugs 64 will preclude such movement. At the same time, the engagement of the lower end of the second setting member 58 with the enlarged portion 65 on the mandrel 18 will prevent downward movement of said second setting member, thus ensuring the operator that the gripping elements 57 will not be prematurely flexed outwardly and protecting the packing body 22 from any force tending to distort the packing body outwardly.

Upon reaching the desired elevation in the well bore, the downward movement of the anchor is halted, and the pipe 11 elevated from the ground surface so as to elevate the mandrel 18 along with the second setting member 58. The friction shoe member 32 will resist such upward movement, however, due to the engagement of the friction shoes 40 with the tubing 10 so that the pin 38 will move into the upper end of the short leg of the ]-slot, abutment of the cap 46 with the collar preventing any possible damaging contact of the pin 38 with the upper end of the J-slot. Then, upon clockwise rotation of the pipe 11, and again the friction shoe member being held stationary by the friction shoes 40, the pin will be moved laterally into alinement with the longer leg of the J-slot 37 and the lugs 64 will be moved into registry with the notches 36, after which the pipe 11 is again lowered. The pin 38 is now free to move downwardly a considerably greater distance, passing under the band 49 if necessary, and accordingly, the downward movement of the pipe 11 and mandrel 18 forces the frustoconical lower end 60 of the second setting member 58 downwardly between the arms 56 of the first setting member, expanding them outwardly and forcing the gripping elements 57 into tight gripping engagement with the interior of the tubing 10. The gripping elements 57 anchor the assembly much more securely in position than the spring shoes 40, and accordingly, as further downward force is applied to the mandrel, endwise thrust is applied to the packing body 22 to distort it outwardly into sealing engagement with the tubing 10 as shown in FIG. 6. A the same time, the end caps 27 bonded to the ends of the packer body 22 and the O-rings 31 ensure against any leakage interiorly of the packing member and protect the member against damage or leakage due to internal seepage.

The pump anchor is now fully set and has sealed off the bore of the tubing 10 so that the well pump may be placed in operation in the usual fashion. At any time, an upward pull may be exerted upon the pipe 11 to reverse the above described operation and release the packer so that it may be removed from the well tubing or moved to a different location therein.

At this point, the lower end of the second setting member 58 is still telescoped by the step 66 and, hence, restrained against full inward flexure to move into gripping engagement with the mandrel. After the packing member 22 is fully set, however, continued downward movement of the mandrel moves the step 66 out from within the lower end of the member 58 while forcing the second setting member farther into the first setting member, causing the intermediate portion of the member 58 to flex inwardly and bringing the slip teeth 63 into locking engagement with the mandrel 18.

The improved version of the pump anchor is shown in FIGS. 12-19, and therein the parts identical to those shown in FIGS. 1-11 have been designated by the same numerals.

In the improved version, the upper end cap for the packer body 22 is replaced by a modified end cap 67 having a tubular sleeve 68 and an annular outwardly and downwardly extending flange 69 much the same as the upper end cap previously described. The end cap 67 differs, however, in that the sleeve 68 carries internal screwthreads 70, and the mandrel 71 differs from the mandrel 18 in that it is provided with external screwthreads 72 for receiving the screwthreads 70. Since the upper end cap 67 is bonded to the packing member 22, the screwthreaded connection between the end cap 67 and the mandrel 71 thus prevents the upper end of the packing member 22 from moving downwardly unless the mandrel so moves, and accordingly, if the packing member encounters parafiin or some other obstruction when the tool is being withdrawn from the tubing, there is provided a protective means for preventing the packing member from inadvertently setting and wedging the tool in the tubing.

The additional improvement in the pump anchor is the provision in the lower end of the step 66 of an annular cuplike ring 73 having an axial bore 74 encompassing the mandrel 71 with its upper end counterbored at 75 to form an annular upstanding flange 76 also surrounding the mandrel but spaced therefrom, The lower periphery 77 of the ring 73 is chamferred, and the ring, which is formed of a hard, high strength, heat-treated alloy steel, is sweated onto the mandrel at the lower end of the step 66. As shown in FIG. 17, the flange 76 is of such dimensions as to receive the lower end 60 of the second setting member 58 and prevent its passage downwardly past the step 66. As shown in FIG. 18, the lower end of the second setting member is spaced above the ring 73 when the pump anchor is in its normally set position, but should the pump anchor be subjected to an excessive downward thrust, as by the breaking of the pump or sucker rods, the cup 73 will receive the lower end of the second setting member, thus limiting its downward travel and precluding oversetting of the anchor to an extent that would prevent its subsequent unsetting and retrieval.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What we claim and desire to secure by Letters Patent is:

1. A pump anchor for well pumps including, an elongate mandrel, first setting means on the mandrel having outwardly facing pipe engaging and gripping elements carried for outward movement, second setting means on the mandrel having inwardly facing mandrel engaging and gripping elements carried for inward movement, the second setting means having a wedge-shaped portion telescoping the first setting means for forcing the gripping elements thereof outwardly and forcing the gripping elements of the second setting means inwardly, friction shoe means carried on the mandrel and connected to one of the setting means, the friction shoe means and first and second setting means forming a setting assembly, locking and unlocking means carried by the friction shoe means and themandrel for limiting movement of the friction shoe means longitudinally of the mandrel, annular packing means surrounding the mandrel, means on the mandrel for forcing the packing means against the setting assembly to distort the packing means into a packing position, and annular cuplike means on the mandrel within the first setting means for receiving the smaller end of the wedgeshaped portion of the second setting means and limiting the telescoping movement thereof into the first setting means to prevent too extreme setting of the pump anchor.

2. A pump anchor for well pumps including, an elongate mandrel, connection means at the upper end of the mandrel for lowering the anchor into a well pipe, annular packing means surrounding the mandrel, friction shoe means slidably mounted on the mandrel, pin and offset slot means carried by the friction shoe means and the mandrel for limiting movement of the friction shoe means longitudinally of the mandrel, first setting means on the mandrel having outwardly facing pipe engaging and gripping elements movably carried for outward movement, second setting means on the mandrel having inwardlyfacing mandrel engaging and gripping elements movably carried for inward movement into engagement with the mandrel, the second setting means having a wedge-shaped portion interposed between the mandrel and the gripping elements of the first setting means for moving said gripping elements outwardly, annular cuplike means on the mandrel within the first setting means for receiving the smaller end of the wedge-shaped portion of the second setting means and limiting the telescoping movment there of into the first setting means to prevent too extreme setting of the pump anchor, one of said setting means being connected to the friction shoe means, means for transferring a longitudinal thrust from the mandrel to one end of the packing means, and means for transferring an opposed longitudinal thrust from one of the setting means to the opposite end of the packing means to distort the packing means into a packing position.

3. A pump anchor for well pumps including, an elongate mandrel, connection means at the upper end of the mandrel for lowering the anchor into a well pipe, annular packing means surrounding the mandrel, friction shoe means slidably mounted on the mandrel, pin and offset slot means carried by the friction shoe means and the mandrel for limiting movement of the friction shoe means longitudinally of the mandrel, first setting means on the mandrel having outwardly-facing pipe engaging and gripping elements movably carried for outward movement, second setting means on the mandrel having inwardly facing mandrel engaging and gripping elements movably carried for inward movement into engagement with the mandrel, the second setting means having a wedge-shaped portion interposed between the mandrel and the gripping elements of the first setting means for moving said gripping elements outwardly, annular cuplike means on the mandrel within the first setting means for receiving the smaller end of the wedge-shaped portion of the second setting means and limiting the telescoping movements thereof into the first setting means to prevent too extreme setting of the pump anchor, one of said setting means being connected to the friction shoe means, means for transferring a longitudinal thrust from the mandrel to one end of the packing means, said end of the packing means being secured to the mandrel, and means for transferring an opposed longitudinal thrust from one of the setting means to the opposite end of the packing means to distort the packing means into a packing position.

References Cited UNITED STATES PATENTS 2,352,423 6/1944 Church 277188 2,630,864 3/1953 Lynes 277--188 2,738,017 3/1956 Lynes 277116.2 3,018,830 1/1962 Springer 166216 3,195,643 7/1965 Harbison et al. 166138 JAMES A. LEPPINK, Primary Examiner.

US. Cl. X.R. 

